Background: The coronavirus disease 2019 (COVID-19) has be designated a pandemic less than 4 months after its first outbreak. Due to the novelty of the virus, there is little understanding of how ecological factors affect transmission of the coronavirus. This study aims to determine the relationship of temperature, absolute humidity, and health infrastructure on COVID-19 transmission and mortality.Methods: Epidemiological data was obtained for all US states and countries worldwide between January 22 and March 23, 2020. Univariate and multivariate linear regressions were done comparing temperature, absolute humidity, and health infrastructure with cases and deaths.Results: The regression models revealed that temperature and humidity significantly affect the number of confirmed cases (p = 0.0123 and p = 0.0072, respectively).Conclusions: The transmission of COVID-19 seems to thrive in colder and drier environments. Despite this relationship, more efforts are needed to ensure compliance to “social distancing” and other public health measures rather than relying on temperature alone to reduce COVID-19 cases.